In a substrate conveyance apparatus used in positioning and conveyance of a substrate in a part mounting apparatus, a screen printing apparatus, etc., both right and left ends of the substrate are placed on upper surfaces of a pair of right and left conveyance belts and the substrate is conveyed. In such a substrate conveyance apparatus, a substrate detection device for detecting that the conveyed substrate reaches a predetermined position is disposed and when this substrate detection device detects that the substrate reaches the predetermined position, control of stopping or decreasing a conveyance speed of the substrate is performed. The substrate detection device includes a projector for projecting inspection light and a light receiver for receiving the inspection light projected from this projector, and detects that the substrate reaches the predetermined position based on a decrease in the amount of received light of the inspection light received by the light receiver when the inspection light is blocked by the substrate conveyed by the substrate conveyance apparatus.
Also, an apparatus constructed so that a substrate can be detected by reflecting inspection light by an inner wall of a hole even when the inspection light is projected in an oblique direction rather than a vertical direction and the inspection light enters the hole since the substrate cannot be detected in a situation in which the inspection light just passes through a hole (for example, a hole for recognizing a position of the substrate or a screw hole for fixing the substrate) disposed in the substrate in a position in which the substrate wants to be detected has been known (Patent Reference 1).    Patent Reference 1: JP-A-6-211334